I recently had iunlock.com update my 9500's firmware from 5.22 to 6.27. First, let me put in a plug for iunlock.com for having very fast service and great communication. I highly recommend them.

When I first got the 9500 back I was experiencing a kern-exec error when trying to use the web browser. A little poking around on some forums and I found that this was not an uncommon occurrence and that a format of the 9500 would resolve it. So after making sure it was backed up I performed the format and the issue is resolved. So far everything seems to be working fine. Web browsing wirelessly seems to be a little quicker now. Things overall seem to be a little faster. Sorry I do not have anything more detailed to report. I am satisfied with the upgrade.